In 1889 industrial age mogul Andrew Carnegie wrote that "the man who dies thus rich dies disgraced." While he made no apologies for income disparities, he argued that it was the responsibility of the wealthy to donate fortunes they had accumulated to worthy causes before their lives were over. In the first half of the 21st century, some researchers estimate between 41 trillion and 136 trillion dollars will be passed on through estates, and not just from the more than 300 families who count themselves among the ranks of America's billionaires.

Has Carnegie's call become part of the American psyche? While only one in ten U.S. households has identified a charity in its will, nine out of ten households make an annual contribution to charitable causes, giving about $1,500 each year on average. Contributions from just the 7 percent of American households who are millionaires account for about half of all charitable donations. However, these households possess 63 percent of the nation's wealth. Also, while giving is less common among poorer families, those with low incomes who do give to charity give generously, donating a higher percentage of their incomes than their middle- and high-income counterparts.

Americans find many ways to contribute to the causes they believe in, including giving to umbrella groups such as the United Way, tithing to religious establishments, or donating directly to secular organizations and causes. Since the 1990s, a growing number of benefactors have been forming giving circles with friends and neighbors to focus and amplify the impact of their donations. Giving circles range in formality from potluck dinners to incorporated nonprofit organizations. They give their participants a direct role in choosing beneficiaries, often sponsor volunteer activities, and usually prompt additional donations to target organizations from their members.